diff mbox

[4/4] firmware: qcom: scm: Move the scm driver to drivers/firmware

Message ID 1424987976-14531-4-git-send-email-galak@codeaurora.org (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Kumar Gala Feb. 26, 2015, 9:59 p.m. UTC
Architectural changes in the ARM Linux kernel tree mandate the eventual
removal of the mach-* directories. Move the scm driver to
drivers/firmware and the scm header to include/linux to support that
removal.

Signed-off-by: Kumar Gala <galak@codeaurora.org>
---
 MAINTAINERS                  |   1 +
 arch/arm/mach-qcom/Kconfig   |   3 -
 arch/arm/mach-qcom/Makefile  |   3 -
 arch/arm/mach-qcom/platsmp.c |   2 +-
 arch/arm/mach-qcom/scm.c     | 344 -------------------------------------------
 arch/arm/mach-qcom/scm.h     |  29 ----
 drivers/firmware/Kconfig     |   4 +
 drivers/firmware/Makefile    |   2 +
 drivers/firmware/qcom_scm.c  | 344 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/qcom_scm.h     |  29 ++++
 10 files changed, 381 insertions(+), 380 deletions(-)
 delete mode 100644 arch/arm/mach-qcom/scm.c
 delete mode 100644 arch/arm/mach-qcom/scm.h
 create mode 100644 drivers/firmware/qcom_scm.c
 create mode 100644 include/linux/qcom_scm.h

Comments

Stephen Boyd Feb. 27, 2015, 6:58 p.m. UTC | #1
On 02/26/15 13:59, Kumar Gala wrote:
> Architectural changes in the ARM Linux kernel tree mandate the eventual
> removal of the mach-* directories. Move the scm driver to
> drivers/firmware and the scm header to include/linux to support that
> removal.
>
> Signed-off-by: Kumar Gala <galak@codeaurora.org>
> ---
>  MAINTAINERS                  |   1 +
>  arch/arm/mach-qcom/Kconfig   |   3 -
>  arch/arm/mach-qcom/Makefile  |   3 -
>  arch/arm/mach-qcom/platsmp.c |   2 +-
>  arch/arm/mach-qcom/scm.c     | 344 -------------------------------------------
>  arch/arm/mach-qcom/scm.h     |  29 ----
>  drivers/firmware/Kconfig     |   4 +
>  drivers/firmware/Makefile    |   2 +
>  drivers/firmware/qcom_scm.c  | 344 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/qcom_scm.h     |  29 ++++
>  10 files changed, 381 insertions(+), 380 deletions(-)
>  delete mode 100644 arch/arm/mach-qcom/scm.c
>  delete mode 100644 arch/arm/mach-qcom/scm.h
>  create mode 100644 drivers/firmware/qcom_scm.c
>  create mode 100644 include/linux/qcom_scm.h

Can you generate this with -M -C? Or just throw

[diff]
        renames = copy

int your git config.

The files are the same right?

> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
> index 41983883..6517132 100644
> --- a/drivers/firmware/Kconfig
> +++ b/drivers/firmware/Kconfig
> @@ -132,6 +132,10 @@ config ISCSI_IBFT
>  	  detect iSCSI boot parameters dynamically during system boot, say Y.
>  	  Otherwise, say N.
>  
> +config QCOM_SCM
> +	bool
> +	depends on ARM || ARM64

No need to have depends on here if the option is hidden. Just make sure
it isn't selected unless the depends are true.

Also, the drivers/firmware/Kconfig file needs to be sourced in the
arch/arm/Kconfig so that we can still get this option on arm (Lina
noticed it isn't working on arm). It looks like arm64 is already
sourcing it.
Kumar Gala Feb. 27, 2015, 9:36 p.m. UTC | #2
On Feb 27, 2015, at 12:58 PM, Stephen Boyd <sboyd@codeaurora.org> wrote:

> On 02/26/15 13:59, Kumar Gala wrote:
>> Architectural changes in the ARM Linux kernel tree mandate the eventual
>> removal of the mach-* directories. Move the scm driver to
>> drivers/firmware and the scm header to include/linux to support that
>> removal.
>> 
>> Signed-off-by: Kumar Gala <galak@codeaurora.org>
>> ---
>> MAINTAINERS                  |   1 +
>> arch/arm/mach-qcom/Kconfig   |   3 -
>> arch/arm/mach-qcom/Makefile  |   3 -
>> arch/arm/mach-qcom/platsmp.c |   2 +-
>> arch/arm/mach-qcom/scm.c     | 344 -------------------------------------------
>> arch/arm/mach-qcom/scm.h     |  29 ----
>> drivers/firmware/Kconfig     |   4 +
>> drivers/firmware/Makefile    |   2 +
>> drivers/firmware/qcom_scm.c  | 344 +++++++++++++++++++++++++++++++++++++++++++
>> include/linux/qcom_scm.h     |  29 ++++
>> 10 files changed, 381 insertions(+), 380 deletions(-)
>> delete mode 100644 arch/arm/mach-qcom/scm.c
>> delete mode 100644 arch/arm/mach-qcom/scm.h
>> create mode 100644 drivers/firmware/qcom_scm.c
>> create mode 100644 include/linux/qcom_scm.h
> 
> Can you generate this with -M -C? Or just throw
> 
> [diff]
>        renames = copy
> 
> int your git config.
> 
> The files are the same right?

Will, do.. I keep forgetting to make this change in .gitconfig

> 
>> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
>> index 41983883..6517132 100644
>> --- a/drivers/firmware/Kconfig
>> +++ b/drivers/firmware/Kconfig
>> @@ -132,6 +132,10 @@ config ISCSI_IBFT
>> 	  detect iSCSI boot parameters dynamically during system boot, say Y.
>> 	  Otherwise, say N.
>> 
>> +config QCOM_SCM
>> +	bool
>> +	depends on ARM || ARM64
> 
> No need to have depends on here if the option is hidden. Just make sure
> it isn't selected unless the depends are true.

While not needed, I’d like to keep it since there is some ARM asm code.

> Also, the drivers/firmware/Kconfig file needs to be sourced in the
> arch/arm/Kconfig so that we can still get this option on arm (Lina
> noticed it isn't working on arm). It looks like arm64 is already
> sourcing it.

will fix

- k
diff mbox

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index ddc5a8c..beb8aa4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1317,6 +1317,7 @@  L:	linux-soc@vger.kernel.org
 S:	Maintained
 F:	arch/arm/mach-qcom/
 F:	drivers/soc/qcom/
+F:	drivers/firmware/qcom_scm.c
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/galak/linux-qcom.git
 
 ARM/RADISYS ENP2611 MACHINE SUPPORT
diff --git a/arch/arm/mach-qcom/Kconfig b/arch/arm/mach-qcom/Kconfig
index 48003ea..2256cd1 100644
--- a/arch/arm/mach-qcom/Kconfig
+++ b/arch/arm/mach-qcom/Kconfig
@@ -22,7 +22,4 @@  config ARCH_MSM8974
 	bool "Enable support for MSM8974"
 	select HAVE_ARM_ARCH_TIMER
 
-config QCOM_SCM
-	bool
-
 endif
diff --git a/arch/arm/mach-qcom/Makefile b/arch/arm/mach-qcom/Makefile
index 10b6841..e324375 100644
--- a/arch/arm/mach-qcom/Makefile
+++ b/arch/arm/mach-qcom/Makefile
@@ -1,5 +1,2 @@ 
 obj-y			:= board.o
 obj-$(CONFIG_SMP)	+= platsmp.o
-obj-$(CONFIG_QCOM_SCM)	+= scm.o
-
-CFLAGS_scm.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1)
diff --git a/arch/arm/mach-qcom/platsmp.c b/arch/arm/mach-qcom/platsmp.c
index 596e623..4b67e56 100644
--- a/arch/arm/mach-qcom/platsmp.c
+++ b/arch/arm/mach-qcom/platsmp.c
@@ -17,10 +17,10 @@ 
 #include <linux/of_address.h>
 #include <linux/smp.h>
 #include <linux/io.h>
+#include <linux/qcom_scm.h>
 
 #include <asm/smp_plat.h>
 
-#include "scm.h"
 
 #define VDD_SC1_ARRAY_CLAMP_GFS_CTL	0x35a0
 #define SCSS_CPU1CORE_RESET		0x2d80
diff --git a/arch/arm/mach-qcom/scm.c b/arch/arm/mach-qcom/scm.c
deleted file mode 100644
index 3e0e334..0000000
--- a/arch/arm/mach-qcom/scm.c
+++ /dev/null
@@ -1,344 +0,0 @@ 
-/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301, USA.
- */
-
-#include <linux/slab.h>
-#include <linux/io.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-
-#include <asm/outercache.h>
-#include <asm/cacheflush.h>
-
-#include "scm.h"
-
-#define QCOM_SCM_ENOMEM		-5
-#define QCOM_SCM_EOPNOTSUPP	-4
-#define QCOM_SCM_EINVAL_ADDR	-3
-#define QCOM_SCM_EINVAL_ARG	-2
-#define QCOM_SCM_ERROR		-1
-#define QCOM_SCM_INTERRUPTED	1
-
-static DEFINE_MUTEX(qcom_scm_lock);
-
-/**
- * struct qcom_scm_command - one SCM command buffer
- * @len: total available memory for command and response
- * @buf_offset: start of command buffer
- * @resp_hdr_offset: start of response buffer
- * @id: command to be executed
- * @buf: buffer returned from qcom_scm_get_command_buffer()
- *
- * An SCM command is laid out in memory as follows:
- *
- *	------------------- <--- struct qcom_scm_command
- *	| command header  |
- *	------------------- <--- qcom_scm_get_command_buffer()
- *	| command buffer  |
- *	------------------- <--- struct qcom_scm_response and
- *	| response header |      qcom_scm_command_to_response()
- *	------------------- <--- qcom_scm_get_response_buffer()
- *	| response buffer |
- *	-------------------
- *
- * There can be arbitrary padding between the headers and buffers so
- * you should always use the appropriate qcom_scm_get_*_buffer() routines
- * to access the buffers in a safe manner.
- */
-struct qcom_scm_command {
-	__le32 len;
-	__le32 buf_offset;
-	__le32 resp_hdr_offset;
-	__le32 id;
-	__le32 buf[0];
-};
-
-/**
- * struct qcom_scm_response - one SCM response buffer
- * @len: total available memory for response
- * @buf_offset: start of response data relative to start of qcom_scm_response
- * @is_complete: indicates if the command has finished processing
- */
-struct qcom_scm_response {
-	__le32 len;
-	__le32 buf_offset;
-	__le32 is_complete;
-};
-
-/**
- * alloc_qcom_scm_command() - Allocate an SCM command
- * @cmd_size: size of the command buffer
- * @resp_size: size of the response buffer
- *
- * Allocate an SCM command, including enough room for the command
- * and response headers as well as the command and response buffers.
- *
- * Returns a valid &qcom_scm_command on success or %NULL if the allocation fails.
- */
-static struct qcom_scm_command *alloc_qcom_scm_command(size_t cmd_size, size_t resp_size)
-{
-	struct qcom_scm_command *cmd;
-	size_t len = sizeof(*cmd) + sizeof(struct qcom_scm_response) + cmd_size +
-		resp_size;
-	u32 offset;
-
-	cmd = kzalloc(PAGE_ALIGN(len), GFP_KERNEL);
-	if (cmd) {
-		cmd->len = cpu_to_le32(len);
-		offset = offsetof(struct qcom_scm_command, buf);
-		cmd->buf_offset = cpu_to_le32(offset);
-		cmd->resp_hdr_offset = cpu_to_le32(offset + cmd_size);
-	}
-	return cmd;
-}
-
-/**
- * free_qcom_scm_command() - Free an SCM command
- * @cmd: command to free
- *
- * Free an SCM command.
- */
-static inline void free_qcom_scm_command(struct qcom_scm_command *cmd)
-{
-	kfree(cmd);
-}
-
-/**
- * qcom_scm_command_to_response() - Get a pointer to a qcom_scm_response
- * @cmd: command
- *
- * Returns a pointer to a response for a command.
- */
-static inline struct qcom_scm_response *qcom_scm_command_to_response(
-		const struct qcom_scm_command *cmd)
-{
-	return (void *)cmd + le32_to_cpu(cmd->resp_hdr_offset);
-}
-
-/**
- * qcom_scm_get_command_buffer() - Get a pointer to a command buffer
- * @cmd: command
- *
- * Returns a pointer to the command buffer of a command.
- */
-static inline void *qcom_scm_get_command_buffer(const struct qcom_scm_command *cmd)
-{
-	return (void *)cmd->buf;
-}
-
-/**
- * qcom_scm_get_response_buffer() - Get a pointer to a response buffer
- * @rsp: response
- *
- * Returns a pointer to a response buffer of a response.
- */
-static inline void *qcom_scm_get_response_buffer(const struct qcom_scm_response *rsp)
-{
-	return (void *)rsp + le32_to_cpu(rsp->buf_offset);
-}
-
-static int qcom_scm_remap_error(int err)
-{
-	pr_err("qcom_scm_call failed with error code %d\n", err);
-	switch (err) {
-	case QCOM_SCM_ERROR:
-		return -EIO;
-	case QCOM_SCM_EINVAL_ADDR:
-	case QCOM_SCM_EINVAL_ARG:
-		return -EINVAL;
-	case QCOM_SCM_EOPNOTSUPP:
-		return -EOPNOTSUPP;
-	case QCOM_SCM_ENOMEM:
-		return -ENOMEM;
-	}
-	return -EINVAL;
-}
-
-static u32 smc(u32 cmd_addr)
-{
-	int context_id;
-	register u32 r0 asm("r0") = 1;
-	register u32 r1 asm("r1") = (u32)&context_id;
-	register u32 r2 asm("r2") = cmd_addr;
-	do {
-		asm volatile(
-			__asmeq("%0", "r0")
-			__asmeq("%1", "r0")
-			__asmeq("%2", "r1")
-			__asmeq("%3", "r2")
-#ifdef REQUIRES_SEC
-			".arch_extension sec\n"
-#endif
-			"smc	#0	@ switch to secure world\n"
-			: "=r" (r0)
-			: "r" (r0), "r" (r1), "r" (r2)
-			: "r3");
-	} while (r0 == QCOM_SCM_INTERRUPTED);
-
-	return r0;
-}
-
-static int __qcom_scm_call(const struct qcom_scm_command *cmd)
-{
-	int ret;
-	u32 cmd_addr = virt_to_phys(cmd);
-
-	/*
-	 * Flush the command buffer so that the secure world sees
-	 * the correct data.
-	 */
-	__cpuc_flush_dcache_area((void *)cmd, cmd->len);
-	outer_flush_range(cmd_addr, cmd_addr + cmd->len);
-
-	ret = smc(cmd_addr);
-	if (ret < 0)
-		ret = qcom_scm_remap_error(ret);
-
-	return ret;
-}
-
-static void qcom_scm_inv_range(unsigned long start, unsigned long end)
-{
-	u32 cacheline_size, ctr;
-
-	asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
-	cacheline_size = 4 << ((ctr >> 16) & 0xf);
-
-	start = round_down(start, cacheline_size);
-	end = round_up(end, cacheline_size);
-	outer_inv_range(start, end);
-	while (start < end) {
-		asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start)
-		     : "memory");
-		start += cacheline_size;
-	}
-	dsb();
-	isb();
-}
-
-/**
- * qcom_scm_call() - Send an SCM command
- * @svc_id: service identifier
- * @cmd_id: command identifier
- * @cmd_buf: command buffer
- * @cmd_len: length of the command buffer
- * @resp_buf: response buffer
- * @resp_len: length of the response buffer
- *
- * Sends a command to the SCM and waits for the command to finish processing.
- *
- * A note on cache maintenance:
- * Note that any buffers that are expected to be accessed by the secure world
- * must be flushed before invoking qcom_scm_call and invalidated in the cache
- * immediately after qcom_scm_call returns. Cache maintenance on the command
- * and response buffers is taken care of by qcom_scm_call; however, callers are
- * responsible for any other cached buffers passed over to the secure world.
- */
-static int qcom_scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf,
-			size_t cmd_len, void *resp_buf, size_t resp_len)
-{
-	int ret;
-	struct qcom_scm_command *cmd;
-	struct qcom_scm_response *rsp;
-	unsigned long start, end;
-
-	cmd = alloc_qcom_scm_command(cmd_len, resp_len);
-	if (!cmd)
-		return -ENOMEM;
-
-	cmd->id = cpu_to_le32((svc_id << 10) | cmd_id);
-	if (cmd_buf)
-		memcpy(qcom_scm_get_command_buffer(cmd), cmd_buf, cmd_len);
-
-	mutex_lock(&qcom_scm_lock);
-	ret = __qcom_scm_call(cmd);
-	mutex_unlock(&qcom_scm_lock);
-	if (ret)
-		goto out;
-
-	rsp = qcom_scm_command_to_response(cmd);
-	start = (unsigned long)rsp;
-
-	do {
-		qcom_scm_inv_range(start, start + sizeof(*rsp));
-	} while (!rsp->is_complete);
-
-	end = (unsigned long)qcom_scm_get_response_buffer(rsp) + resp_len;
-	qcom_scm_inv_range(start, end);
-
-	if (resp_buf)
-		memcpy(resp_buf, qcom_scm_get_response_buffer(rsp), resp_len);
-out:
-	free_qcom_scm_command(cmd);
-	return ret;
-}
-
-u32 qcom_scm_get_version(void)
-{
-	int context_id;
-	static u32 version = -1;
-	register u32 r0 asm("r0");
-	register u32 r1 asm("r1");
-
-	if (version != -1)
-		return version;
-
-	mutex_lock(&qcom_scm_lock);
-
-	r0 = 0x1 << 8;
-	r1 = (u32)&context_id;
-	do {
-		asm volatile(
-			__asmeq("%0", "r0")
-			__asmeq("%1", "r1")
-			__asmeq("%2", "r0")
-			__asmeq("%3", "r1")
-#ifdef REQUIRES_SEC
-			".arch_extension sec\n"
-#endif
-			"smc	#0	@ switch to secure world\n"
-			: "=r" (r0), "=r" (r1)
-			: "r" (r0), "r" (r1)
-			: "r2", "r3");
-	} while (r0 == QCOM_SCM_INTERRUPTED);
-
-	version = r1;
-	mutex_unlock(&qcom_scm_lock);
-
-	return version;
-}
-EXPORT_SYMBOL(qcom_scm_get_version);
-
-#define QCOM_SCM_SVC_BOOT			0x1
-#define QCOM_SCM_BOOT_ADDR			0x1
-/*
- * Set the cold/warm boot address for one of the CPU cores.
- */
-int qcom_scm_set_boot_addr(u32 addr, int flags)
-{
-	struct {
-		__le32 flags;
-		__le32 addr;
-	} cmd;
-
-	cmd.addr = cpu_to_le32(addr);
-	cmd.flags = cpu_to_le32(flags);
-	return qcom_scm_call(QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_ADDR,
-			&cmd, sizeof(cmd), NULL, 0);
-}
-EXPORT_SYMBOL(qcom_scm_set_boot_addr);
diff --git a/arch/arm/mach-qcom/scm.h b/arch/arm/mach-qcom/scm.h
deleted file mode 100644
index 6bb84cf..0000000
--- a/arch/arm/mach-qcom/scm.h
+++ /dev/null
@@ -1,29 +0,0 @@ 
-/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-#ifndef __QCOM_SCM_H
-#define __QCOM_SCM_H
-
-#define QCOM_SCM_FLAG_COLDBOOT_CPU1		0x01
-#define QCOM_SCM_FLAG_COLDBOOT_CPU2		0x08
-#define QCOM_SCM_FLAG_COLDBOOT_CPU3		0x20
-#define QCOM_SCM_FLAG_WARMBOOT_CPU0		0x04
-#define QCOM_SCM_FLAG_WARMBOOT_CPU1		0x02
-#define QCOM_SCM_FLAG_WARMBOOT_CPU2		0x10
-#define QCOM_SCM_FLAG_WARMBOOT_CPU3		0x40
-
-extern int qcom_scm_set_boot_addr(u32 addr, int flags);
-
-#define QCOM_SCM_VERSION(major, minor) (((major) << 16) | ((minor) & 0xFF))
-
-extern u32 qcom_scm_get_version(void);
-
-#endif
diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
index 41983883..6517132 100644
--- a/drivers/firmware/Kconfig
+++ b/drivers/firmware/Kconfig
@@ -132,6 +132,10 @@  config ISCSI_IBFT
 	  detect iSCSI boot parameters dynamically during system boot, say Y.
 	  Otherwise, say N.
 
+config QCOM_SCM
+	bool
+	depends on ARM || ARM64
+
 source "drivers/firmware/google/Kconfig"
 source "drivers/firmware/efi/Kconfig"
 
diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 5373dc5..3fdd391 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -11,6 +11,8 @@  obj-$(CONFIG_DMIID)		+= dmi-id.o
 obj-$(CONFIG_ISCSI_IBFT_FIND)	+= iscsi_ibft_find.o
 obj-$(CONFIG_ISCSI_IBFT)	+= iscsi_ibft.o
 obj-$(CONFIG_FIRMWARE_MEMMAP)	+= memmap.o
+obj-$(CONFIG_QCOM_SCM)		+= qcom_scm.o
+CFLAGS_qcom_scm.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1)
 
 obj-$(CONFIG_GOOGLE_FIRMWARE)	+= google/
 obj-$(CONFIG_EFI)		+= efi/
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
new file mode 100644
index 0000000..6e7a72b
--- /dev/null
+++ b/drivers/firmware/qcom_scm.c
@@ -0,0 +1,344 @@ 
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/qcom_scm.h>
+
+#include <asm/outercache.h>
+#include <asm/cacheflush.h>
+
+
+#define QCOM_SCM_ENOMEM		-5
+#define QCOM_SCM_EOPNOTSUPP	-4
+#define QCOM_SCM_EINVAL_ADDR	-3
+#define QCOM_SCM_EINVAL_ARG	-2
+#define QCOM_SCM_ERROR		-1
+#define QCOM_SCM_INTERRUPTED	1
+
+static DEFINE_MUTEX(qcom_scm_lock);
+
+/**
+ * struct qcom_scm_command - one SCM command buffer
+ * @len: total available memory for command and response
+ * @buf_offset: start of command buffer
+ * @resp_hdr_offset: start of response buffer
+ * @id: command to be executed
+ * @buf: buffer returned from qcom_scm_get_command_buffer()
+ *
+ * An SCM command is laid out in memory as follows:
+ *
+ *	------------------- <--- struct qcom_scm_command
+ *	| command header  |
+ *	------------------- <--- qcom_scm_get_command_buffer()
+ *	| command buffer  |
+ *	------------------- <--- struct qcom_scm_response and
+ *	| response header |      qcom_scm_command_to_response()
+ *	------------------- <--- qcom_scm_get_response_buffer()
+ *	| response buffer |
+ *	-------------------
+ *
+ * There can be arbitrary padding between the headers and buffers so
+ * you should always use the appropriate qcom_scm_get_*_buffer() routines
+ * to access the buffers in a safe manner.
+ */
+struct qcom_scm_command {
+	__le32 len;
+	__le32 buf_offset;
+	__le32 resp_hdr_offset;
+	__le32 id;
+	__le32 buf[0];
+};
+
+/**
+ * struct qcom_scm_response - one SCM response buffer
+ * @len: total available memory for response
+ * @buf_offset: start of response data relative to start of qcom_scm_response
+ * @is_complete: indicates if the command has finished processing
+ */
+struct qcom_scm_response {
+	__le32 len;
+	__le32 buf_offset;
+	__le32 is_complete;
+};
+
+/**
+ * alloc_qcom_scm_command() - Allocate an SCM command
+ * @cmd_size: size of the command buffer
+ * @resp_size: size of the response buffer
+ *
+ * Allocate an SCM command, including enough room for the command
+ * and response headers as well as the command and response buffers.
+ *
+ * Returns a valid &qcom_scm_command on success or %NULL if the allocation fails.
+ */
+static struct qcom_scm_command *alloc_qcom_scm_command(size_t cmd_size, size_t resp_size)
+{
+	struct qcom_scm_command *cmd;
+	size_t len = sizeof(*cmd) + sizeof(struct qcom_scm_response) + cmd_size +
+		resp_size;
+	u32 offset;
+
+	cmd = kzalloc(PAGE_ALIGN(len), GFP_KERNEL);
+	if (cmd) {
+		cmd->len = cpu_to_le32(len);
+		offset = offsetof(struct qcom_scm_command, buf);
+		cmd->buf_offset = cpu_to_le32(offset);
+		cmd->resp_hdr_offset = cpu_to_le32(offset + cmd_size);
+	}
+	return cmd;
+}
+
+/**
+ * free_qcom_scm_command() - Free an SCM command
+ * @cmd: command to free
+ *
+ * Free an SCM command.
+ */
+static inline void free_qcom_scm_command(struct qcom_scm_command *cmd)
+{
+	kfree(cmd);
+}
+
+/**
+ * qcom_scm_command_to_response() - Get a pointer to a qcom_scm_response
+ * @cmd: command
+ *
+ * Returns a pointer to a response for a command.
+ */
+static inline struct qcom_scm_response *qcom_scm_command_to_response(
+		const struct qcom_scm_command *cmd)
+{
+	return (void *)cmd + le32_to_cpu(cmd->resp_hdr_offset);
+}
+
+/**
+ * qcom_scm_get_command_buffer() - Get a pointer to a command buffer
+ * @cmd: command
+ *
+ * Returns a pointer to the command buffer of a command.
+ */
+static inline void *qcom_scm_get_command_buffer(const struct qcom_scm_command *cmd)
+{
+	return (void *)cmd->buf;
+}
+
+/**
+ * qcom_scm_get_response_buffer() - Get a pointer to a response buffer
+ * @rsp: response
+ *
+ * Returns a pointer to a response buffer of a response.
+ */
+static inline void *qcom_scm_get_response_buffer(const struct qcom_scm_response *rsp)
+{
+	return (void *)rsp + le32_to_cpu(rsp->buf_offset);
+}
+
+static int qcom_scm_remap_error(int err)
+{
+	pr_err("qcom_scm_call failed with error code %d\n", err);
+	switch (err) {
+	case QCOM_SCM_ERROR:
+		return -EIO;
+	case QCOM_SCM_EINVAL_ADDR:
+	case QCOM_SCM_EINVAL_ARG:
+		return -EINVAL;
+	case QCOM_SCM_EOPNOTSUPP:
+		return -EOPNOTSUPP;
+	case QCOM_SCM_ENOMEM:
+		return -ENOMEM;
+	}
+	return -EINVAL;
+}
+
+static u32 smc(u32 cmd_addr)
+{
+	int context_id;
+	register u32 r0 asm("r0") = 1;
+	register u32 r1 asm("r1") = (u32)&context_id;
+	register u32 r2 asm("r2") = cmd_addr;
+	do {
+		asm volatile(
+			__asmeq("%0", "r0")
+			__asmeq("%1", "r0")
+			__asmeq("%2", "r1")
+			__asmeq("%3", "r2")
+#ifdef REQUIRES_SEC
+			".arch_extension sec\n"
+#endif
+			"smc	#0	@ switch to secure world\n"
+			: "=r" (r0)
+			: "r" (r0), "r" (r1), "r" (r2)
+			: "r3");
+	} while (r0 == QCOM_SCM_INTERRUPTED);
+
+	return r0;
+}
+
+static int __qcom_scm_call(const struct qcom_scm_command *cmd)
+{
+	int ret;
+	u32 cmd_addr = virt_to_phys(cmd);
+
+	/*
+	 * Flush the command buffer so that the secure world sees
+	 * the correct data.
+	 */
+	__cpuc_flush_dcache_area((void *)cmd, cmd->len);
+	outer_flush_range(cmd_addr, cmd_addr + cmd->len);
+
+	ret = smc(cmd_addr);
+	if (ret < 0)
+		ret = qcom_scm_remap_error(ret);
+
+	return ret;
+}
+
+static void qcom_scm_inv_range(unsigned long start, unsigned long end)
+{
+	u32 cacheline_size, ctr;
+
+	asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
+	cacheline_size = 4 << ((ctr >> 16) & 0xf);
+
+	start = round_down(start, cacheline_size);
+	end = round_up(end, cacheline_size);
+	outer_inv_range(start, end);
+	while (start < end) {
+		asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start)
+		     : "memory");
+		start += cacheline_size;
+	}
+	dsb();
+	isb();
+}
+
+/**
+ * qcom_scm_call() - Send an SCM command
+ * @svc_id: service identifier
+ * @cmd_id: command identifier
+ * @cmd_buf: command buffer
+ * @cmd_len: length of the command buffer
+ * @resp_buf: response buffer
+ * @resp_len: length of the response buffer
+ *
+ * Sends a command to the SCM and waits for the command to finish processing.
+ *
+ * A note on cache maintenance:
+ * Note that any buffers that are expected to be accessed by the secure world
+ * must be flushed before invoking qcom_scm_call and invalidated in the cache
+ * immediately after qcom_scm_call returns. Cache maintenance on the command
+ * and response buffers is taken care of by qcom_scm_call; however, callers are
+ * responsible for any other cached buffers passed over to the secure world.
+ */
+static int qcom_scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf,
+			size_t cmd_len, void *resp_buf, size_t resp_len)
+{
+	int ret;
+	struct qcom_scm_command *cmd;
+	struct qcom_scm_response *rsp;
+	unsigned long start, end;
+
+	cmd = alloc_qcom_scm_command(cmd_len, resp_len);
+	if (!cmd)
+		return -ENOMEM;
+
+	cmd->id = cpu_to_le32((svc_id << 10) | cmd_id);
+	if (cmd_buf)
+		memcpy(qcom_scm_get_command_buffer(cmd), cmd_buf, cmd_len);
+
+	mutex_lock(&qcom_scm_lock);
+	ret = __qcom_scm_call(cmd);
+	mutex_unlock(&qcom_scm_lock);
+	if (ret)
+		goto out;
+
+	rsp = qcom_scm_command_to_response(cmd);
+	start = (unsigned long)rsp;
+
+	do {
+		qcom_scm_inv_range(start, start + sizeof(*rsp));
+	} while (!rsp->is_complete);
+
+	end = (unsigned long)qcom_scm_get_response_buffer(rsp) + resp_len;
+	qcom_scm_inv_range(start, end);
+
+	if (resp_buf)
+		memcpy(resp_buf, qcom_scm_get_response_buffer(rsp), resp_len);
+out:
+	free_qcom_scm_command(cmd);
+	return ret;
+}
+
+u32 qcom_scm_get_version(void)
+{
+	int context_id;
+	static u32 version = -1;
+	register u32 r0 asm("r0");
+	register u32 r1 asm("r1");
+
+	if (version != -1)
+		return version;
+
+	mutex_lock(&qcom_scm_lock);
+
+	r0 = 0x1 << 8;
+	r1 = (u32)&context_id;
+	do {
+		asm volatile(
+			__asmeq("%0", "r0")
+			__asmeq("%1", "r1")
+			__asmeq("%2", "r0")
+			__asmeq("%3", "r1")
+#ifdef REQUIRES_SEC
+			".arch_extension sec\n"
+#endif
+			"smc	#0	@ switch to secure world\n"
+			: "=r" (r0), "=r" (r1)
+			: "r" (r0), "r" (r1)
+			: "r2", "r3");
+	} while (r0 == QCOM_SCM_INTERRUPTED);
+
+	version = r1;
+	mutex_unlock(&qcom_scm_lock);
+
+	return version;
+}
+EXPORT_SYMBOL(qcom_scm_get_version);
+
+#define QCOM_SCM_SVC_BOOT			0x1
+#define QCOM_SCM_BOOT_ADDR			0x1
+/*
+ * Set the cold/warm boot address for one of the CPU cores.
+ */
+int qcom_scm_set_boot_addr(u32 addr, int flags)
+{
+	struct {
+		__le32 flags;
+		__le32 addr;
+	} cmd;
+
+	cmd.addr = cpu_to_le32(addr);
+	cmd.flags = cpu_to_le32(flags);
+	return qcom_scm_call(QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_ADDR,
+			&cmd, sizeof(cmd), NULL, 0);
+}
+EXPORT_SYMBOL(qcom_scm_set_boot_addr);
diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
new file mode 100644
index 0000000..6bb84cf
--- /dev/null
+++ b/include/linux/qcom_scm.h
@@ -0,0 +1,29 @@ 
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#ifndef __QCOM_SCM_H
+#define __QCOM_SCM_H
+
+#define QCOM_SCM_FLAG_COLDBOOT_CPU1		0x01
+#define QCOM_SCM_FLAG_COLDBOOT_CPU2		0x08
+#define QCOM_SCM_FLAG_COLDBOOT_CPU3		0x20
+#define QCOM_SCM_FLAG_WARMBOOT_CPU0		0x04
+#define QCOM_SCM_FLAG_WARMBOOT_CPU1		0x02
+#define QCOM_SCM_FLAG_WARMBOOT_CPU2		0x10
+#define QCOM_SCM_FLAG_WARMBOOT_CPU3		0x40
+
+extern int qcom_scm_set_boot_addr(u32 addr, int flags);
+
+#define QCOM_SCM_VERSION(major, minor) (((major) << 16) | ((minor) & 0xFF))
+
+extern u32 qcom_scm_get_version(void);
+
+#endif